1. Field of the Invention
The present invention relates generally to a cellular mobile communication network in digital mobile communication systems, and in particular, to a method and apparatus for providing commercial broadcasting services in the cellular mobile communication network.
2. Description of the Related Art
The communication-related environment in both the conventional and future communication systems is and will be changing very rapidly in both fields of wireless and wired communication systems over international networks as well as in local networks. In general, mobile communication systems refer to different telecommunication systems providing personal wireless data transmission while the subscribers roam the system area. In addition to conventional speech transmission, the digital mobile communication systems provide a diversity of other services: short message services, broadcasting service, data transmission, etc. Of these, the data transmission service particularly provides a mobile subscriber with a chance of wireless Internet access to almost all data services of fixed networks. In particular, the third generation of mobile communication systems, e.g., the IMT-2000 (International Mobile Telecommunication-2000) system, should be implemented with more integrated communication environments most suited to provide the mobile subscriber with the diversity of information services, on a real time basis, as well as the speech and picture transmissions in the conventional meaning. Further, the recent and rapid developments in the technology of mobile communication systems, later cilia, mobile communication terminals or mobile phones, e.g., cellular phones, PCS (Personal Communication Service) phones, or IMT-2000 terminals, are trending toward providing mobile subscribers with a variety of information/data transmission services via wireless Internet access on their mobile terminals, as well as the conventional speech communications.
FIG. 1 shows a schematic diagram illustrating the structure of a wireless communication system in a conventional cellular communication network. Referring to the structure, a total serviceable area on the cellular communication network generally consists of a plurality of smaller service areas, i.e., cells 102a and 102b, in the center of which cells a base station 110a or 110b is respectively positioned to communicate various speech/data traffic and control signals with mobile stations 120 within each assigned cell via a wireless interface. FIG. 2 shows the structure of a wireless channel formed between a base station 110 and a mobile terminal 120, wherein a channel 1 established in the direction from the base station 110 toward the mobile terminal 120 is referred to as a downlink channel, while another channel 2 established in the direction from the mobile terminal 120 toward the base station 110 is referred to as an uplink channel.
In the meantime, digital television systems, that are designed in general to convert picture images into digital data for transmission to its receiver end on a real time basis and to receive the transmitted digital data for reproduction of the picture images on a digital television receiver, have been recently developed up to an intelligent apparatus capable of servicing various digital data information formats as well as the conventional transmission and reproduction of picture images and audio signals. In particular, the recent technical development in this field of the art, i.e., digital television systems, allows more effective compression of the moving picture images into compatible digital data for high speed and high quality data transmission on a real time basis together with more abundant contents of information, even on a commercial scale. Transmission and reception of these digital picture images of information could be provided with cable or satellite television systems as well as over-the-air broadcasting systems.
As a result, therefore, a variety of techniques have been devised in the art to utilize the respective advantages of the digital mobile communication system and the digital television system to the maximum degree, while making the most effective connection or combination between these two systems. The result of several researches carried out to date reveals that the transmission of digital moving picture images of information to mobile communication terminals in the future mobile communication systems will most probably be provided through a supplemental channel proposed for a packet data service. The supplemental channel is a kind of dedicated traffic channel for mutual communications between a specified base station and a mobile terminal only.
If a service provider should intend to provide its mobile subscribers with any television broadcasting service on a non-commercial basis, then every mobile terminal would be permitted to access the downlink traffic channel in the direction from the base station to the mobile terminals. On the other hand, if the service provider should intend to provide the mobile subscribers with any television broadcasting service on a commercial or profitable basis, it would then be required that only authorized mobile terminals are allowed to access such a specified television broadcasting service and unauthorized terminals would not be allowed access. The use of known broadcasting service techniques available in the conventional mobile communication systems, however, usually allows its broadcasting traffic channel to be accessed by every desired mobile terminal without specific limitation, thereby failing to prevent the unauthorized subscribers from appropriating the specified broadcasting traffic channel.